Vinyl esters and vinyl ester interchange process



Patented Sept. 29, 1942 UNITED STATES PATENT OFFICE VINYL ESTERS ANDVINYL ESTER INTEBCHANGE PROCESS Loring Goes, Jr.. Brookiield, Mam,minor, by

mesne assignments, to E.

I. du Pont de Nemonrs & Company, Wilmington, Del., a corporation ofDelaware I No Drawing.

11 Claims.

The invention relates to esters and a process for producing them.

One object -of the invention is to provide an expeditious and facilemethod of synthesizing certain esters. Another object of the inventionis to produce a new class of polymers. Another object of the inventionis to produce certain new of producing certain esters, which methodgives superior yields. Another object of the invention is to producecertain esters more cheaply.

Another object of the invention is to produce a relatively hard organicbond for grinding wheels and other abrasive products. Another object ofthe invention is to provide a colorless optical resin which is hardenough to resist most types of abrasion met with in actual practice.Other objects will be in part obvious or in part pointed outhereinafter.

The invention accordingly consists in the combinations of elements, inthe molecular structure, and in the several steps and relation and orderof each of said steps to one or more of the others thereof, all as willbe illustratively described herein, and the scope of the application ofwhich will be indicated in the following claims.

A mercury sulphate catalyst suspended in acetic acid was made bydissolving grams of red HgO in 100 cc. of glacial acetic acid followedby subsequent precipitation with 6.6 cc. of concentrated sulphuric acidat a temperature of 85 C. The catalyst was allowed to settle and thesupernatant acetic acid was drawn off by suction. A volume ofmethacrylic acid equal to the volume of acetic acid remaining with thecatalyst (60 cc.) was then added and the catalyst again allowed tosettle and the supernatant liquid drawn I oil. This procedure wasrepeated until the flask contained 6b. of acetic acid and 105 cc. of

'methacrylic acid. Two hundred cubic centimeters of methacrylic acid and200 cc. of vinyl acetate together with 2 grams of pyrogallol as aninhibitor were then added, and the mixture was stirred at roomtemperature for one hour. At the end. of this time the catalyst hadcompletely dissolved. The mixture was then allowed to stand fortwenty-four hours at room temperature and was then poured into water.The acids were neutralized with sodium carbonate. The mixture of esterswas extracted with ether and the ether solution dried over sodiumsulphate.

Application February 23, 1939, Serial No. 257,961

The solution was then fractionated and the fractions collected are=shownin the following table:

Quantity Boiling point (i'ubictgre'nii- D me (1) Vinyl acetate 25 4252 lg r im.) (2 Vinyl methacrylata; 40 42-62 mm. 8 lgtllgylllgenedia:ettate.fi 10 -75 15 min.

yi eneace eme acry ate. it 65-75 6 mm.

(5) Ethylidene dimethacrylate 20 8040 (6 In similar fashion I can takeany vinyl ester and react it with any organic acid in the presence of areaction catalyst capable of catalyzing the production of such vinylester from acetylene and synthesize in a single reaction threeethylidene glycol esters and a vinyl ester different from the startingvinyl ester. In the above table It polymerizes readily to a hardtransparent mass which is useful for the production of optical bodies,the manufacture of inter-layer glass material, for windows and the like,and as a bond .for abrasive articles. It is not only clear, colorlessand transparent but also somewhat flexible and can be molded to desiredshapes. It may be modified with various cross-linking agents, forexample with vinyl methacrylate or ethylidene dimethacrylate which werementioned in the foregoing table. In order to produce an interpolymer ofethylidene acetate methacrylate with a suitable cross-linking agent, themonomeric substances are mixed. Suitable cross-linking agents have aplurality of polymerizable double or triple bonds and when ethylideneacetate methacrylate is polymerized with one of them, a polymer resultswhich is harder than ethylidene acetate methacrylate itself. Suitablecross-linking agents for polymerizable unsaturated methacrylatecompounds are disclosed in copending applications of Samuel S. Kistlerand Carl E. Barnes, filed January 28, 1938, Serial Nos. 187,546, 187,547and 187,548, and also copending applications of Carl E. Barnes, filedJanuary 30, 1939,

i an Serial Nos. 253,624 and 253,625. The cross-linking agents disclosedin the application Serial No. 187,546 are the esters of acrylic ormethacrylic acids with ethylene glycol, diethylene glycol, triethyleneglycol, glycerol, pentaglycerol, triglycerol, pentaerithritol, manitol,and allyl alcohol. The cross-linking agents disclosed in the applicationSerial No. 187,547 are the above and also acrylic and methacryllc acids.The cross-linking agents disclosed in the application Serial No. 187,548include the allyl esters of acrylic and methacrylic acids. In the Barnesapplications, Serial Nos. 253,624 and 253,625, the anhydrides of acrylicand methacrylic acids are shown to be effective cross-linking agents.All of these applications are owned by the assignee of my presentinvention. Furthermore, the ethylidene acetate methacrylate may have itsindex of refraction changed by the addition thereto of styrene or otherindex modifiers. In application Serial No. 206,684, filed May 7, 1938,by Carl E. Barnes, the acrylic and methacrylic acid esters of thehydroxyquinolines, the nitrophenols, the chlorophenols, triphenyl methylmethacrylate, styrene, nitro-ethylene, ortho nitro styrene, meta nitrostyrene, and para nitro styrene are specifled as suitable index ofrefraction modifiers. In the application of Carl E. Barnes, Serial No.253,625, filed January 30, 1939, some of the above index refractionchanging agents are mentioned and also others, such as vinyl chloride,vinyl acetate. furyl vinyl ketone, and triphenyl benzene. In theapplication of Carl E. Barnes, Serial No. 254,228, filed February 2,1939, the following soluble, inert, non-polymerizable, organic compoundswhich are suitable for modifying the refractive index of polymers suchas those of the present invention are given:

Compound Naphthal n Aoengpbflmna Anthmmmn 1I;henanti1rene yrene-Trlphenylbenzene Chlorinated naphthalenel-chloroanthraoeneQ-ethyianthracene Alpha methyl anthracene 1,6-nsphthylenediamine1,8-naphthylen Algha naphthylamine Et yl bets naphthylamine Ethyl alphanaphthylamine Diemethyl In another application of Carl E. Barnes, SerialNo. 254,229, filed February 2, 1939, there is disclosure of some of theabove compounds to change the index of refraction of transparent resinsand also ortho hydroxy diphenyl methacrylate, the copolymer of vinylacetate and vinyl chloride, methyl vinyl ketone, methyl isopropenylketone, diphenyl ketone, and phenyl vinyl ketone.

access? The above applications also are ownedby the assignee of thepresent invention.

Of the two above-mentioned polymerizable esters which are suitablecross-linking agents, the ethylidene dimethacrylate is believed to be anovel composition of matter but is claimed in my prior copendingapplication Serial No. 239,533, filed November 8, 1938.

As examples of other vinyl esters which may be substituted for vinylacetate in the process of the example given above, and to produce othernovel ethylidene glycol esters, I may use vinyl acetate, vinyl formate,vinyl propionate, vinyl butyrate or vinyl chloroacetate.

In place of methacrylic acid I may use any organic acid, for examplepropionic, butyric, acrylic and substituted acrylic acids other thanmethyl, for example ethyl. It should be understood, however, that inorder to obtain ethylidene glycol esters which are polymerizable, I usepolymerizable acids such as acrylic and substituted acrylic acids. Theprocess of my invention, however, may be employed to produce other thanpolymerizable compounds.

As catalysts other than mercuric sulphate, I may use other mercuricsalts or boron trifiuoride, but any catalyst which is capable ofcatalyzing the product of the starting vinyl ester from acetylene may beused.

As identification of the substances shown in the table, I give thefollowing formulae identified by the numbers which will be found in thetable:

1 cn,-coocn=on, 2 CHFCCOOCH=GH9 H5 era-coo cn-cn,

cm-ooo pa -coo CH-OH.

OHF C-O 0 0 HQ CHFb-C O O Oil-43B;

CEs=CO O O In the formula,

' cm-coo cit-cm CE=G-CO0 H. I may substitute hydrogen or any other alkylgroup for the methyl group of the bottom line. Furthermore, in'the topline of the formula I may substitute hydrogen or any alkyl group for themethyl group. Any such substituted products will likewise bepolymerizable.

It will thus beseen that there has been provided by this invention anovel method and novel compositions of matter in which the variousobjects hereinabove set forth together with many thoroughly practicaladvantages are successfully achieved. As various possible embodimentsmight be made of thecompositions of the above invention and as theartherein-described may be varied in various parts, all withoutdeparting from the scope of the invention, it is to be understood thatall matter hereinbefore set forth is 3. As a composition of matter,monomeric ethylidene acetate acrylate,

CHr-COO cHFcn-c'oo I 4. As a composition of matter, monomeric CHz-COO\CHI-CH;

CH1=0RCOO where R is selected from the group consisting of hydrogen andmethyl.

5. As a composition of matter, the polymer produced by polymerizing themonomer of claim 4.

6. As a composition of matter, monomeric CHI-CH;

CHFCf-OOO I where R is selected from the group consisting oi hydrogenand methyl and R is selected from the group consisting of hydrogen andalkyl.

7. As a composition of matter, the polymerproduced by polymerizing themonomer of claim 6.

8. Process of producing esters in a single reaction which comprisesusing a catalyst capable of catalyzing the production of a vinyl esterof a carboxylic acid from a carboxylic acid and, acetylene, and reactinga vinyl ester of a carboxylic acid with methacrylic acid in the presenceof such catalyst" and thereby producing three ethylidene glycol estersand vinyl methacrylate.

9. Process of producing esters in a single reaction which comprisesusing a catalyst capable of catalyzing the production of a vinyl esterfrom a carboxylic acid and acetylene, and reacting vinyl acetate withmethacrylic acid in the presence of such catalyst and thereby producingthree ethylidene glycol esters and vinyl methacrylate.

10. Process of producing esters in a single reaction which comprisesreacting vinyl acetate with methacrylic acid in the presence 01' amercury salt as a catalyst and thereby producing three ethylidene glycolesters and vinyl methacrylate.

11. Process of producing esters in a single reaction which comprisesreacting vinyl acetate with methacrylic acid in the presence of borontrifluoride as a catalyst and thereby producing three ethylidene glycolesters and vinyl methacrylate.

LORING CQES, Jn.

